Musannaf Ibn Abi Shayba 3:1310

Ya'la ibn 'Ubayd narrated to us, he said: Isma'il ibn Abi Khalid narrated to us, from 'Imran ibn Abi al-Ja'd, who said: I was with Ibn 'Umar on a journey, and he led us in the Fajr prayer, and he recited for us: "When the sun is wrapped up [Idha al-shamsu kuwwirat]."